Heating furnace



May 29,' 192s. 1,671,147

B. E. 1 DE MARE HEATNG FURNACE Filed NOV. 22, 1924 ATTORNEYS,

Patented May 29, 1928.

BALTZAR E. L. DE MAR, I? PHILADELPHIA, PENNSYLVANIA.

HEATING FURNACE.

Application led November 22, 1924. Serial No. 751,439.

rifhe object of my invention is to provide means for adapting an ordinary hot air, hot water or steam heating furnace, designed especially to burn the larger' size coal, to elliciently burnthe smaller sized hard coal as well soft coal. The invention, however, may be adapted te any type of furnace.

lliy invention involves means for the supply of air both to the coal bed land directly to the combustion chamber above the coal bed to insure the Combustion ofthe combustible gases as' they leave the coal bed.

In accordance with my invention there is provided a tube carrying the air from a blower, and adapted to extend upwardsy through a coal bed. The tube is provided with a circular' opening in or adjacent to the grate, which (in'addition to the air that may be supplied' through the grate) furnishes the oxygen required for the fuel combustion zone. The air from the blower lindsits way through the ash bed outwards, while the air from the grate (if any be admitted through the grate) is more apt to follow the walls,

.the combination resulting in an even distribution of the air for the combustion zone. A numberl of small 4holes are drilled through the wallof the tube, where it passes through the coal bed. These are for the purpose of extending the combustion zone through the center of the coal bed and thus provide at the top of the coal bed the heat necessary to ignite the combustible gas rising from the coal. The oxygen for burning the gas is supplied by air, issuing from .a circular orifice in the tube above the fuel bed, at more or less approximately right angles to the gas rising from the coal, thus causing a quick and intimate mixture for the combustion of this gas and also having the effect of directing the resulting fiame towards the walls of the combustion chamber and thus providing' for a better and more ecient heat transfer to the medium, whether water or air which carries away and distributes the heat from the furnace.

The air from the blower keeps the tube from being overheated, and in doing so, is itself preheated, thus increasing` the heat-ing efficiency of the furnace. to protect the tube, where it is exposed to a high degree of temperature, it may also be calorized7 or protected with a fire clay sleeve against damage from being overheated.

In order further Y A preferred embodiment of the invention is shown inthe `accompanying drawings, in which- F ig. 1 is a plan view of a furnace, with the top removed, and equipped with a device embodying my invention.v Fig. is a Side view, partially in section, of a furnace equipped with a. device embodying my invention. Fig. 3 is a sectional view showing a detail of construction.

Referring to the drawings, a indicates a furnace provided with a grate lll having a fuel chamber c and anrash pit d, and provided with a fuel feed opening having a door f. g is a door for the ash'pit below the door f and h is a flanged lit-ting to which a suitable smoke pipe may be connected.

Exterior to the furnace is an air blower 10 adapted to force air through a feed pipe 11 (composed of as many sections as may be convenient), the end of the feed pipe extending upward through the grate and terminating, preferably, at or near what, in practice, would beV the level of the ash bed. On the pipe 11 is a perforated sleeve valve 12, which is turnable by hand on the pipe into position to bring its perforations more or less into, or entirely out of, alignment with corresponding perforations in the pipe 11.` By this means, air may be introduced, if desired, in regulatable quantities, into the ash pit, which air passes up through the grate 14. in the usual manner. Vithin the pipe 11 is a hand-operablev valve 13, by which the volume of air passing through pipe 11 may be regu-- lated. The volume of air passing through pipe 11 may also be regulated by varying the speed of the blower 10, or by regulating the damper on the blower' inlet.

Supported on the pipe 11, by means of brackets 15, is a hood 16, provided with perforations 160. The hood causes air passing upward from the pipe 11 to be diverted laterally adjacent the upper surface of the grate or fuel support 14. The air escapes from the annular passage formed between the top of pipe 11 and the rim of hood 16. Overlying the grate 14 and surrounding the pipe 11 is an imperforate plate 17, which prevents air from blowing ashes downwardly through the grate into the ash pit.

Mounted on the hood 16 is a pipe 18 which is provided with perforations through which air escapes laterally into the fuel bed.y

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On the upper' end of pipe 18 is slidably mounted a sleeve 19, which is held in any adjusted position `by means of a set screw 20. Sleeve 19 carries brackets Q1, to which is secured a hood 22. Air escapes laterally and obliquely from between the hood and the top of the pipe 18. It is this airA which is vmainly relied upon to effect combustion of the combustible gases that arise from the fuel bed. When the blower is not operating, suliicient air for slow combustion may be obtained by the natural draft of the furnace inducing air through the inlet opening of lthe blower.7 the volume of this air being regulatedby the damper shown in the inlet opening.

1n the operation of the furnace equipped with a device embodying my invention7 it will be noted that air for the combustion of the fuel bed, supported on the grate, is supplied mainly through pipe 11 and it will bev understood` that, if desirable, in using the finer sizes of coal` a solid support for the fuel` bed may be provided instead of the.

usual form of grate illustrated in the drawings. f

In, operation, air supplied through pipe 11 is inY part diverted laterally adjacent the upper surface of the grate by means of the perforations 16., thus providing for conibustion of the fuel on the grate; Air passing up through the'perforated pipe 18` in part passes out through the preforations cans ing combustion of the fuel immediately surrounding the pipe. The balance of the air in pipe 18 passes out at the upper end and is diverted downwardly into the fuel bed by Y theho0d22 causing the gases rising from then fuel bed to burn. The gases rising from tion, it is notmy intention-that my invention shall be limited thereto, since various modilicati'ons in detail of structure may be made `without departing from the spirit of my invention.

Having now fully described my invention, what I claim and desire to protect by Letters Patent is: f

1. In a heating furnace the combination with a grate, an air inlet pipe extending from outside the furnace upward through the grate, a second' pipe extending upward through the fuel chamber above the grate, means lbetween said pipes to distribute air above the grate, and means above the second pipe. to, distribute airla'bove the fuel bed7 said second pipe being perforated for the passage of" airinto the fuel bed.

2. The combination defined in claim 1 characterized bythe vprovision of means inassociation with the air pipe whereby a regulated amount of air may bel supplied therei through.

In testimony of which invention,l I have hereunto set my hand, at Philadelphia, Pcnnsylvkmi'a,V on this 23rd day of October, 1924.

BALTZAR E. L. DE MAR. 

